C# is a versatile, high-level programming language developed by Microsoft, primarily used for developing applications on the .NET framework. It is object-oriented and supports a wide range of programming paradigms, including imperative, functional, and event-driven programming. C# is the primary language for building Windows applications, as well as for game development with Unity. It also supports cross-platform development through .NET Core, making it suitable for web, mobile, and cloud applications. C# is known for its simplicity, strong type safety, and powerful development tools, making it a favorite among developers in various fields.